Non-invasive biosensing technologies have enormous potential for several medical, fitness, and personal well-being applications. The sweat ducts can provide a route of access to many of the same biomarkers, chemicals, or solutes that are carried in blood and can provide significant information enabling one to diagnose ailments, health status, toxins, performance, and other physiological attributes even in advance of any physical sign. Sweat has many of the same analytes and analyte concentrations found in blood and interstitial fluid. Interstitial fluid has even more analytes nearer to blood concentrations than sweat does, especially for larger sized and more hydrophilic analytes (such as proteins).
While bio-monitoring fluids offer their greatest potential when used a source of continuous information about the body, the technological challenges of accomplishing such continuous monitoring are considerable. For example, many techniques that work well in a laboratory are difficult to implement in a wearable device. This is especially true for laboratory techniques used to measure analytes that typically emerge in sweat, interstitial fluid, or other fluid below the detection limit for available sensors. To overcome this challenge, devices and methods for concentrating fluid samples inside a wearable device are needed, and disclosed herein.
Many of the drawbacks and limitations stated above can be resolved by creating novel and advanced interplays of chemicals, materials, sensors, electronics, microfluidics, algorithms, computing, software, systems, and other features or designs, in a manner that affordably, effectively, conveniently, intelligently, or reliably brings biofluid sensing technology into proximity with a fluid as it is generated.